The instant invention relates to a protective housing made of a synthetic material to hold measuring, control, monitoring and similar devices in repeated use under tightly sealed conditions.
In chemical and refining plants, field instruments such as measuring transducers are generally built into protective housings made of a synthetic material to protect these instruments from climatic conditions and aggressive substances and thus to ensure their proper operation and long tool life.
Such protective housings are known in a great number of designs. Current configurations consist mostly of a box-type element which is open on one side and of a cover element which overlaps and tightly closes the first element in the manner of a hat in repeated use with the intercalation of seals.
In another design (AGCO Company, The Netherlands, Instrument Protection System) a box-type protective housing is divided into two housing elements along the diagonals of the lateral surfaces so that either housing element is in the form of a roof or three-edged prism with an open base surface with an all-around juxtaposition rim.
The two housing elements are, however, of somewhat different configurations, so that the expense for the manufacture of two different molds must be incurred, as well as the expense for storing, shipping, etc., two different housing elements.
Hardware such as hinges or quick-release locks is apparently attached directly on the housing wall without any further supports and wall reinforcements, so that their strength may not be sufficient under conditions of strenuous use and rough handling in the field.
Space-saving stacking of individual housing elements into each other does not appear to be possible as no inclination of lateral surfaces can be discerned. Stacks of some height would in any case be out of the question because of lacking stack supports since the weight would be transferred to an excessive extent upon the rather thin walls of the housing elements at the bottom of the stack. Since the housing elements do not have a symmetric roof shape as a rule, the center of gravity would furthermore shift to the outside of the support surface so that the stack could no longer stand on its own. Stacking, storing and packaging is therefore expensive and difficult for the manufacturer as well as for the buyer.
The tightness and stability of the closed housing could also be improved to advantage.
Accordingly, an object of the instant invention is to create a protective housing that can be produced simply and inexpensively, and can be stacked easily and put to general use.